Knockdown box.



F. W. KEITH. K'NocKnowN Box.` APPLICATION FILED NOV. I8. 1912.

v Patented Nov. 2

2 SHEETS-SHE I.

44.1.1 Il! l1 F. W. KEITH.

KNOCKDOWN BOX.

APPLICATION FILED Nov. 18, 1912.

Patented Nov. 2, 1915.

2 SHEETS-SHEET 2- Illinois, ful Improvements in Knockdown Boxes,

FRED WILDER KEITH, 0E CHICAGO, ILLINOIS.

KNOCKDOWN BOX. l

Specification of Letters Patent.

Application led November 18, 1912. Serial No. 731,983.

To all whom t may concern:

Be it known that I, FRED WILDER KEITH', a citizen of the United States, residing at Chicago, in the county of Cook and State of have invented certain new and use o which the following is a specification.

This invention relates to improvements in separable or knock-down woodenfboxes and box shown in Fig. 1, showing the two joints between the upper margins ofthe end walls Aand the top wall of the box. Fig. 3 isaJ like enlarged sectional view of the joint between one of the end walls and the bottom wall of the box. Fig. 4 is a view of the meeting margins offthe end and bottom walls as illustrated in Fig. 3, separated from each other. Fig. 5 is a sectional vi'ew of the meeting edges of one of the side walls and lthe top wall of the box, separated from each other. Fig. 6 is a detail side elevation of one corner of the end wall of the box'. Fig. 7 is a sectional view of the same, taken upon line 7 7 of Fig. 6. Fig. 8 is a section of the same, taken upon line A8--8 of Fig. 6. Fig. 9 is a view showing -t e inner face of lone corner of the end wall f the box. Fig. 10 is a perspective view of one corner of the top wall of the box. Fig. 11 is a perspective view of one of the upper corners of the side wall of the box. Fig. 12 is a perspective view, as seen from the outside of one of the vupper corners of the end wall of the box. 4 Fig. 13 is a perspective viewof one cornerof the bottom wall of the box. Fig 14 is a perspective view of one corner of the box shown in Fig. 1, illustrating the method of assembling the bottom, end and'side walls.

' Fig. 15 is a sectional view of the meeting edges of two of the two box walls showing a modified construction in the joint strips. Figs. 16 and 1'1' are like sectional viewsillus- 'ftrating still another modification of the joint strips.

Asshown in said drawings, A indicates and have clamping engagement side walls, andA3 the top wall of a wooden knock-downbox. The bottom A is provided at itslends with sheetmetal joint strips B B; '.lhe ends A1 A1 are provided with bottom v joint strips C C adapted to interlock with the strips BB and have lateral joint strips C1 C1, and a top joint strip C2. The sides A2 A2 have end joint strips D D adapted to interlock with the joint strips C1 C1. The

top A? is provided at its ends with jointstrlps E E adapted to interlock with the joint strips C2 C2. The bottom A is provided at its side margins with joint strips F F forming grooves to receive the lower margins of the side walls, and the top A3 haslike'joint strips Gr Gr forming grooves' to@ recelve the upper margins of the said side walls. Said joint strips are made of folded strips of sheet metal, the marginal parts of the bottom, A1 A1 the end walls, A2 A2 lthe iatentea Noma, i915.

which embracethe margins of the wooden U parts or walls to which they are attached same, while their central parts are folded upon each other and shaped to form flanges which project from the edges of the walls and areadapted for interfitting or intel'-` locking engagement with each other, except at the side edges of the bottom and top walls where the flanges on said joint strips for-m grooves to receive the said upper and lower margins ofthe side walls. i lThe construction of the joint strips by which the bottom, side and end walls are united with each other is shown in section in Figs.A 3 and 4, in connection with the joint strips the end wall is joined to the adjacent end margin of the. bottom wall. The said strips B and C are folded along their central parts to form doublefthick anges b c that project from the edges of the wall to which the strips are attached, while the marginal parts of the strips are arranged to embrace the marginal parts of the wall and have clamping engagement therewith. In the case of .the strip B, the folded-flange is hollow and of dove-tail shape and its marginal part b1adjacent to the inner face of the wall-A isinserted in a slit or groove extending in.- wardly fromfthe edge of the wall parallel with its inner face, while the exterior marginal part b2 of the stripy extends over the outer face of the lwall A, and its free edge is depressed or indented into the wood so as to with the B and C, by which the lower edge of bring said marginal part b2 into convergent relation with the part b1 thereby affording a firm clamping engagement of the parts b1 b2 with the part of the wall between them. The hollow flange b is located adjacent to the inner face of the wall A, and the innerA fold of the metal forming it is parallel with the inner face of the wall and preferably in line with the marginal part b1 of the strip B.

'The outer fold of said flange b is obliquely arranged, so as to give dove-tail shape to the flange. The outer marginal part b2 of the strip B is. united with the exterior folded part of the flange Z) at the base of the latter by-means of a transversely extending part b3 which overlies the end surface of the wall A and merges into the said outer marginal part b2 by a right angled bend. As a further means of securely fastening the joint strip to the wall, the strip is shown as provided in its outer marginal part b2 with the inwardly bent prongs, cut from the sheet metal, as shown 'at b4 in Figs. 3 and 4. In the case of the jointstrip C, its folded part constituting the flange c is bent into hookform to constitute an inwardly facing dove tail groove adapted to receive the dove-tail flange b of the joint strip B. Said strip C has its inner and outer marginal parts 01 c2 arranged in the same manner as the corresponding parts b1 b2 of the joint strip B. The flange c of the strip C is formed by the central part of the strip, which is folded together to give a double thickness of metal in the flange. Said flange is arranged adjacent to the outer face of the end wall A1 and its inner fold is connected with the marginal part c1 by a transversely bent or extending part c3 which rests against the edge of the end wall. The outer edge of the flange c is bent inwardly into oblique relation to the plane of the wall, and forms with the transversely extending part c3 of the strip, a groove of dove-tailed form adapted to receive the correspondingly shaped flange b. The outer marginal part c2 of saidjoint strip C is, moreover, provided with holding prongs c4 cut from the said part and extend# ing into the wall in the same manner as in the case of the joint strip B.

When the parts are interlocked by the engagement of the flange I) with the groove formed by the flange c, said flange b overlaps the margin of the end wall and bears at its inner face against the part c3 of the strip C, while thehooked marginal part of the flange c extends into bearing contact with the transverse part b3 of the strip B. The interlocking parts of joint strips are thus brought substantially within the planes of the outer faces of the box walls, and the joints are made without any parts which project outside of the outer surfaces of the' The folded parts of the joint strips which constitute the interlocking flanges, are made with aminimum number of bends in their folded parts, while said folded parts are relatively narrow, so that the marginal parts of the strips are held from spreading apart and will firmly hold or clamp the margins of the wooden walls, while the flanges themselves are made stiff or rigid and are, therefore, adapted to retain the form originally .given them bythe machine used in their margins are covered by the parts of the walls which extend over the inserted margins of the strips, a constructionas provided by which the inner marginal parts of the wooden walls meet each other, this construction having the advantage that the box has a continuous interior surfacei'of Wood for contact with the contents ofthe box, so that, if the box be used for fruit or other commodity liable to corrode the metal strips, the contents of the box will be prevented from coming in contact with any part of said strips.

The lateral joint strips C1 C1 and the top joint strips C2 on the end walls yAl Al are made like the joint strips C, while the end joint strips D D on the side walls A2 are like the joint strips B B on the ends of the bottom wall. The bottom and side walls of the box thus constructed will be joined to the end wall by slipping the locking flanges on the ends of the bottom wall into engagement with the corresponding flanges of the bottom strips C C of the end wall, and by likewise inserting the locking flanges on the ends of the side walls into engagement with the corresponding flanges on the lateral margins of the end walls.

The meeting margins of the side walls, bottom wall and top wall are initered or beveled at their meeting edges, as clearly seen in Fig. 5. By this construction, said bottom, side and top walls are held by their engagement with each other in proper relative position or from sliding on the end wall. That is to say, assuming the-bottorn wall to be first eonnectedwith the end walls, and the side walls then inserted into place, the engagement of the mitered meeting edges of the bottom and side walls will result- 1n holding said bottom wall from sidewise movement and in yholding the side walls from slipping downwardly past the edges of the `bottom wall. The method of assembling the parts is clearly illustrated in Fig.

14 wherein thev bottom wall A is shown as extending from the end wall, and the side wall A2 isv partially elevated above its norp mal position.

Thelateral joint strips F and G on the bottom and top walls are alike, and the construction thereof will be understood from a description of one` of the top-wall joint strips Gr which is illustrated in Fig. 5. Said joint strip G extends along and is secured to theside margin of the top wall and shaped to form a vertical flat flange g which projects downwardly and is adapted to form with the beveled \or mitered edge of the top wall, a groove to receive the mitered upper margin of the sidewall A1. Said joint strip Gr is shown as connected with the top wall in the same manneras hereinbefore described. That is to say, the central part of said strip is folded together along its central part to form the flange g, its marginal part g1 overlaps the outer face of the top wall, and its marginal part g2 extends along the inner face of the beveled edge of said top wall and has its edge g3 inserted in a slit or groove formed in said top wall between its inner and outer faces. G, arranged as described, forms, with the beveled edge of the top wall, a V-shaped groove to receive the beveled top margin of the side wall and serves, by the arrangement of its flange g with the outer face of said side wall to hold said side wall from springing outwardly away from the top wall,

' joint strips.

while the stiffness imparted to the' edge of the top wall by said strip Gr, which extends from end to end of the saine, serves to prevent the margin of the top wall from springing 'or bending outwardly away from the side wall.

The strips G G on the lateral edges of the top wall and the like strips F F on the bottom wall are, moreover, shown as additionally secured to the said walls by means of holdingprongs as indicated by g4 in Fig. 5, cut from the outer marginal parts of the strips and entering the surface of the wooden wall. y A Y The top wall A3, when arranged to engage at its side edges with the side walls A2 A2 in the manner described, will have its end joint strips, E E so constructed that they may be placed in vlocking engagement with the joint strips C2 C2 on the end walls, without endwise sliding movement of "said As shown in the drawings, said, joint strips E E are connected with the ends of the top wall in thesame manner as before described in' connection with the other oint stripswillustrated,.and they have fianges e formed by folding together the parts of the joint strips which extend outwardly from the ends of the top wall, as hereinbefore described, but said flanges e instead of being 'of dove-tailed form are fiat The said joint strip and inclined upwardly and outwardly so that they will be adapted for interlocking f lowering the elevated end of the top wall j until the flange e thereon is carried beneath and interlocked with the flange c at the same end of the box as shown in full lines in said Fig. 2.` In this operation, downward pressure is brought upon the strip E onV the downwardly moving edge of the top wall suflicient to force said flange e past the flange c when the lower inclined surface of the flange e is in contact lwith the upper inclined surface of the flange 0,' the top edge of the end wall being sprung outwardly far enough to permit the said flange e to slip past the edge of the flange c and enter beneath the same.

The top and bottom joint strips C C2, and the end joint strips C1 C1 on the end wall of the box are rigidly joined or connected with each other at their ends,\so that the four l'jointstrips will constitute inefl'ect a rigid metal frame surrounding the end wall and giving great strength or rigidity thereto. Likewise, the .two end joint strips B B on the bottom wall are rigidly joined at their ends tov t-he lateral joint strips F: F on said bottom wall, and the end joint strips E E of the top wall are rigidly joined at their ends to the lateral joint strips .G Cr on the lateral margins Vof 'the top wall.`

The construction of the partsv atrtlie meeting ends of saidjointistrips on the end wall is'illustrated inwFigs. 6 to 9, in connection with the joint strips C C1 at the bottom and one end margin of the end wall, and in Fig.

12, in connection with the joint strips C1 C2 at the end and top of said end wall. As clearly seen in Figs. 6, 7 and 8, the meeting ends of the outer marginal parts of the said strips C and C1, which extend over the outer if:

said strips C C1 are joined by means of. L;

tongues c cut from lthe strip G and extending through vslots in the strip C1 and bent over on the outer 'face of said strip C1, as clearly seen in Figs. 7 and 8 and also illustrated in connection with the upper joint strip Cfand end joint strip C1 in Fig. 12. By means of the tongue c, the ineeting'ends of the joint strips are rigidly secured together. vTo further strengthen the connection between the meeting ends of the joint strips, the end of the outer marginal part of the joint lstrip C, which extends beneath the corresponding outer part of the joint strip C1, is, as clearly shown in Figs. 6 and 8, extended into the folds of the flange c, and reaches to the base of the hooked end of said fiange. Said end ofthe joint strip C, being confinedl in the fold ofthe strip C1, afirm andvrigid joint is afforded between the ends of said strips C C?.

The end margin of the inner fold of the fla-nge c, including the transverse part 03, and the inner marginal part 01 which extends into the edge of the box wall, Ais made oblique or mitered, and the end margin of the corresponding parts ofsthestrips C is correspondingly mitered; the mitered end margins meeting each other at the corner of the wall, as clearly seen in Fig. 9.f The inner parts or folds of the folded joint strips `are thus mitered"a.t their ends, while the outer parts or folds overlap each other "and are rigidly joined together. At all of the corners of t-he end wall, moreover, the inturned or hooked edges of the locking flanges on the joint strips C C1 and C2 are cut away at their ends, so as to leave openings, in line with the grooves formed by said oint strips,

for the lateral insertion of the flanges on the side and bottom walls, as clearly seen in.,

Figs. 9 and 12.

. At the corners of the bottom wall, the

ends of the joint strips B where they join the oblique or mitered side edges of said bottom wall are beveled, as shown in Fig. 13, so as to substantially coincide with the beveled marginal surface of the said bottom wall, and the oblique part f1 of the strip F which fits against said beveled surface. Likewise in the case of the corners of the top wall, the ends ofthe flanges g on the joint strips G are beveled or inclined to'corre- `spond with the inclination of the beveled side edges of said top wall and to coincide with the inclined parts g2 on the joint strip G, as clearly seen in Fig. 10. In the case of said bottom and top wal/ls, themeeting ends of the joint strips B and Fin onecase and E and GrJ in the other case are overlapped, and joined by tongues cut from the ends of one of the strips and passing through slots in the other strip. This construction is shown in Fig. 1, wherein the ends of the lateral joint strips Gr Gr enter beneath the ends of the joint strips E E, 'and said joint strips G are provided with tongues g5 lwhich pass through slots in the ends of the strips E, and are bent downwardly over the same, so as to aord a strong interlocking connection between said joint strips Eand G.

The inner folds or marginal parts of the joint strips B and F which are inserted edgewise into the bottom wall are miteredmeaaae `projecting tongues Z1 which are folded inwardly over the beveled surfaces atvthe top and botto-m edges of said side wall, and are pressed firmly against or embedded in said beveledsurfaces so as to be substantially flush therewith. The tongues all thus constitute hooked ends on the strips which serve to bind or confine the tapered or beveled margins of the side walls to the joint strips, and to afford a strong and firm connection between the ends of said joint strips, and the said side wall. By the employment of said hooked shaped tongues d1 on the ends of the end joint strips D, therefore, not only are the side margins of the side -wallvfirmly connected to the joint strips outwardly to the extreme margins of the beveled edges of said side walls, but the ends of the joint strips D D are brought into solid bearing contact with the flanged joint strips F and Gr on the bottom or top walls,

Figs. 15, 16 and 17.

As illustrated in Fig.15 the meeting edges of two box walls H and I are shown, the same being provided with sheet metal joint strips J and K. In this instance the meeting edges of the box walls H and. I are beveled at their inner parts and meet each other in the manner of a mitered joint, and the joint strips J and K are'folded along their central parts to form locking flanges j and 7c. In this instance, the flange 7' is made of L-'shape, while the outer edge of the-flange k is made of hook-shape, so asto embrace the transversely extending marginal part of the L shaped flange j. The inner marginal parts jl k1 of the joint strips-in this in stance extend inwardly along vthe beveled surfaces of the walls H and I. The edge of the marginal part jl is bent inwardlj7 against the inner surface of the wall H and vthe inner marginal part of the part lol is extended into the wood of the wall I at a distance from the inner surface of said wall.

L OU

Said wall I is thicker than thewall H and the edge of its tongue z', formed by the wood which projects past the margin of the part k2 of the joint strip K is at right an. gles to the inner face ofthe'wall, and adapted to meet or abut against the inner face of the wall H, so as to cover the edge of i the part jl and prevent the Vcontents of the box from coming in contact with the inner marginal parts of either of the joint strips,

. as indicated in dotted lines in Fig. 15.

In Figs. 16 and 17 I have shown joint strips generallyl like -those illustrated in Fig. 15. In this case, the two walls L, 'M are provided with joint strips N, O, having anges n o. The flange n' is bent into hookform in cross-section, and the flange o is likewise bent into hook-form, vand has the' edge of its inturned marginaly partlocated at such distance from its base, as'to give 'room for insertion of the hooked end of the flange n while the parts 'n.1 o1 extend inwardly overv the beveled meeting edges of the walls L and M. In this c'ase, the interlocking lia-nges n `0 may be engaged with each other either -bv slipping the flange n endwise into the ange o or by bringing the hooked flange n into engagement with the Hange o .when the walls \L, M are in line with each other as shown in Fig. 16 and then swinging the two lwalls into position at right angles to each other, as shown in.

Fig. 17. I

' The walls may be connected in the manner last described in joining the bottom with the end walls of the box 'but in connecting Vthe side walls with said end wall it'is necessary that the side walls be slipped into place after the bottom and end walls have been joined.

An important vadvantage is gained by the employment ofthe joint strips which em-v brace or are clamped upon the marginal parts of `wooden box walls and are provided with interlocking flanges for the rea-v son that by this construction, a very' strong and rigid box may b'e made by the use of thin wood or, veneer. Such box, therefore, may be light in weight, and made by the use of a ,small quantity of wood, with consequent saving in Vcost of material. The joint strips havingclamping engagement with the edges of the thin pieces of wood forming the boxwalls serve to stiien and strengthen the same and prevent the splitting of the wood. It wi1l,-of course, be understood that in the case of the side walls of the box, the grain of the wood will run endwise, and the end joint strips will extendtransversely of-the grain of the wood.

An important advantage is gained in the case of a box wall having four ljoint strips' by rigidly connecting the joint strips with A each other at the corners of said wall, for

the reason that by thisA construction 'any Vof the joint strips J and K, shown in splitting or breaking of the wall cannot take place withoutbreaking or rupturing thev metal joint strips. Said joint strips, being of sheet meta-l and bent into a shape which gives them great f strength and rigidity," form with the wooden walls to which they given stiffnessV to withstand bending stressesacting obliquelv onthe strips, because of the inclined parts of the joint strips, such as are formed by -the inwardly .bent outer margin of the ange c in Figs; 3 and 4, 4by the oblique part of the dove-tailed portion of the flange b in said Figs. 3 and 4, by the oblique parts'f1 g1 of the strips F and- G, (Figs. 10 and 13) by the .oblique parts k1 1g. 15, and by the similar oblique parts n1 01 of the joint strips N and O'shown in Figs. 16

and 17. Said oblique parts form in effect obliquely disposed stitfening members adapted to resistbending stresses or strains acting obliquely on the corners of the box.

- It will be noted that in the case of each form.. of joint shown in which two joint strips yunite the meeting edges of the box walls -by interlocked engagement, the interlock is so formed as to effectually stifl'en the box and prevent it from 'permanent distortion by lracking movement. That is to say, in the case of each pair of cooperating 'joint strips, they are so constructed that they'have rigid abutting shoulder portions' which engage 'each `other at or near the-interior angle .formed by the meeting inner surfaces of thebox walls and also have other abutting and interlocked parts which are outwardly remote from the first mentioned shoulders so that change of angularvrelation of the box walls in a. direction toward each other, or in such manner as toreduce the angle between their inner surfaces to less thalra right angle, is prevented. Obviously, if this condition be secured in all of the four parallel corners or angles of the box,

considered either transversely around the box or lengthwise around the box, then the box -cannot be distorted or ra ked in that particular "direction, and, if joints' be thus rigid'both ways around the box, rigidity against racking orl distortion, in any possible direction, within thejlimits of stiflf ness of said flanges, is insured.

While I have throughout this vspecification used the term rigidly as describing the character of union formed bythe oint strips described, yet I do not wish this term to be understood in its literal or absolute sense, inasmuch `as it is obvious that these joint strips, formed of resilient sheet metal shaped to form flanges of double thickness, as described, afford a certain amount of resilience and have some capacity for movement relatively to each other without perlnanently distorting the box or the joint strips, and without in any sense weakening the union. This capacity to yield under abnormal stresses, so far from being a disadvantage, constitutes a distinct and im' portant feature of advantage of the invention. That is tosay, in the case of .a box heavily loaded being dropped, or otherwise beingbrought into violent contact With a practically unyielding object, such for example, as'a pavement, it will be Aobvious that a certain 'amount of elasticity or capacity for yielding must be provided for, or the box will be broken or the joints ruptured; an inelastic or rigid body being more easily broken by impact than an elastic one. l havefound'by practical demonstrationI that heavily loaded boxes constructed in accordance with thepresent invention may be subjected to extraordinary concussion both upon the corners and flatwise upon the ends or sides and yet withstand such concussion withoutl injury or permanent distortion. This result is clearly due to the limited, but sufficient, degree of resiliency inherent to the double-thick interlocked flanges of the joint strips having. the characteristics set forth.

I claim as my invention: l. lin a box, two walls and means uniting said walls in right angled relation, comprising joint strips applied to the meeting edges of the respective walls, each strip being formed of resilient sheet metal and folded upon itself longitudinally and having its lateral marginal portions separated and embracing and clamping a substantial portion of the 'margin of the box wall to which it is applied, and also having'its central folded portion formed into a double-thick locking flange, saidflanges being shaped to interlock 'with each other, and said joint stri s having substantially non-yielding abutting portions which engage each other at or near the interior angle of intersection of the inner surface of the box walls, and the flanges having interfittin'g engaging portions outwardly distant from said abutting parts', whereby i the box walls are united and locked against change of angular relation in a direction toward each other, rigidly within the limit of stiffness of said flanges.

2. In a box, a wall provided -with a sheet metal joint strip applied to the edge of said wall, saidvstrip being folded upon itself lon- `gitudinally and having its lateral marginal portions separated 'and arranged to embrace the outer faces of the walls.

clamped upon the margins of the\walls, and

the central parts of which are folded, to-

gether and shaped to form interlocking flanges, the flange'of one case extending in the plane of the wall to which it is attached substantially in line with the outer face of the wall and being bent inwardly at its margin to form, with the part of the strip that extends over the edge of the wall, ay flange receiving groove, and the flange in the other case extending in the plane of the wall to which it is attached at a distance inwardly from the outer face ofthe wall and being bent at its margin toward the outer face of the wall to engage the inwardly bent marginal part of the flan'gevon the other Wall,y

the flanges when interlocked'roccupying the space exterior to themeeting edges of the walls and substantially within the planes of of which extends obliquely inward to form,

with the transverse part of the strip which extends inwardly from the base of the flange over the marginal surface of the wall, a dove-tailed groove, and the other strip being folded upon itself to form a hollow dove tailed flange adapted to engage said groove, said dove-tailed flange projecting from the margin of the other wall and having its in` ner face parallel with the inner face of the wall, its base at adistance inwardly from the outer surface of the wall, and its outer face obliquely disposed.

5. The lcombination with two box-walls of wood or the like, of folded joint strips, the marginal parts of which embrace the marginal parts of the walls and the central 'Ill parts of which are folded together and shaped to form interlocking flanges, the inner marginal part of eachystrip being extended into the wall to which it is attached between the side faces thereof and the marwood or the like, of'folded joint strips, the marginal parts of which embrace the marginal parts of the walls and the central parts of which are lfolded together and shaped to form interlocking flanges, the flange in one case extending from the edge of the wall adjacent to the outer face thereof and being bent inwardly at its margirto form, with the part of the strip that extends over the edge of the wall, a flange receiving groove, and the flange in the other case extending from the edge of the Wall to which it is attached at a distance from the outer face thereof and being bent at its margin toward the said outer face of the wall; the inner marginal part of each strip being extended into the Wall to which it is attached between the side faces thereof and the marginal parts of the walls inside of said inner marginal parts of the strips meeting each other to cover the joint strips.

7. The combination of end wallsprovided on similar edges with joint strips and two other walls which meet each other at their side edges and are provided at their ends with joint strips which interlock with those on the end Walls; each pair of interlocking joint strips being shaped to form, in one instance, a flange receiving groove and, in the other instance, a flange adapted to be slid endwise into said groove; the meeting side edges of said walls being mitered, and

one of them being provided with a oint strip having a flange adapted to form, -with the mitered face of the wall to which it is attached, a groove to receive the mitered side edge of the other wall.

8. The combination with two box-Wallsv of wood or the like, offolded joint strips, the marginal parts of which embrace the marginal parts of the walls and the central parts of which are folded together and shaped to form interlocking flanges, both of said joint strips embracing obliquely extending parts adapted to stiffen the joint lin a manner to withstand oblique strains.

9. A box wall of woo'd or the like, provided withl four sheet metal joint strips folded at their central parts to form flanges which project from'the edges of the wall and the marginal parts efwhich embrace the marginal parts of the wall, the ends of said joint strips being overlapped and rigidly secured to each other at the corners of the wall.

10. A box wall of wood or the like, provided with four sheet metal joint strips folded at theirl central parts to form flanges which lproject from the edges of the Wall and the marginal parts of which embrace the marginal parts of the wall, the marginal parts of the ends of said strips, at one` side of the wall, being overlapped and rigidly secured together at the corners of the wall.

11. A box wall of wood or the like, pro--V vided with four sheet metal joint strips folded at their central parts to form flanges which project from the edges of the wall and the marginal parts of which embrace the marginal parts of the wall, the marginal parts of the ends of said strips at one -side of the wall meeting each other at the corners of the box in overlapped relation, and the overlapping parts at each corner being provided one with a locking tongue andthe other with a slot toreceive said tongue.

12. A box wall of wood or the like, proi parts of -the ends o-f said strips at one side.

of the wall meeting each other atthe cornersy of the wall in overlapping relation, and the end portion of one of the marginal parts at each corner extending beneath the end portion'of the marginal part of the other strip and between the folded parts constituting the flange on such other strip.

13. A box wall of wood or the like, provided with four sheet metal oint strips folded at their central parts to form flanges which project from the edges of .the wall,

andthe marginal parts of which embrace the marginal parts of the wall, the marginal parts of the ends of said joint strips at the outer face-of the wall being overlapped and rigidly joined to each other attheir meeting ends, and the marginal parts of the joint strips at the inner face of the Wall being mitered at their meeting end s.

14. The combination with a box-wall of wood or the like, which is beveled or mitered at its side edges, of joint strips on the ends of said wall, the central parts of which form locking flanges which `project from the end margins of the wall and the marginal parts of which embrace the marginal parts of the wall, and joint strips on the-.beveled side margins of said wall, the'cefitral parts of which are folded together to form flanges at right angles to the outer face of the Wall,

which form, With'the beveled edges of the walls, V-shaped grooves, and the marginal parts of which embrace the saidI beveled edges o-f the Wall.

15. The combination with a box wall of wood or the like, which is beveled or mitered at its side edges, of joint strips on the said side edges, the central parts of which are folded together to form flanges which project at right anglesto the outer face of the wall and form, with its beveled' edges, V- shaped grooves, and the outer marginal p'arts of which extend over the outer face' of the wall and the inner marginal parts of which extend over the beveled edges of the wall.

16. The combination of end walls provided with joint strips, and bottom, top and side walls provided at their ends with joint strips which interlock with those on the end walls, the top, bottom and side walls being mitered at their meeting edges, and the bottom and top walls being provided at their side edges with joint strips having ,flanges adapted'to form, with their mitered edges, grooves to receive the bottom and top margins of the side walls, and which consists ofl folded strips of metal, the central parts of whlch are folded to form said flanges, the marginal parts of which embrace the marginal partsy of the said bottom and top walls, and the inner marginal parts of which fit'against the mitered'edges of said bottom and top walls, and have their edges inserted into the beveled edges of said bottom and top walls between the inner and outer faces thereof.

beveled or mitered marginal side edges ofv vthe said wall.

18. A box wall of wood or the like, which is beveled or mitered at its side edges, and provided at its end margins with metal joint strips, said metal joint strips being folded at their central parts to form locking flanges which project from the end margins of the wall, and the lateral parts of which embracel the marginal parts of the wall, the said joint strips being provided at the ends of their outer marginal parts with tongues which are bent inwardly over the beveledor mitered marginal side edges of the said wall, and the inner marginal parts of said joint strips being inserted. edgewise into said wall between the inner and outer faces thereof.

19. The combination ofl end walls providedeach with four joint strips, the central parts of which are folded to form locking flanges, the marginal parts of which embrace the marginal parts of the said end walls, and the ends of which are rigidly connected with each other at the corners of said end walls, bottom,top and side walls, which are mitered attheir meeting' side edges, said bot-- tom and top walls being provided each at `its end and side margins with joint stripsithe l central parts of which are folded to form Lwaaae flanges, and the marginal parts of which embrace the marginal parts ofthe wall and the ends of which are rigidly connected with each other at the corners of said wall, the flanges on the end joint strips of said bottom and top walls being adapted to interlock with the flanges of the joint strips on thebend walls, and the flanges on the side margins of said bottom and top walls being adapted to form grooves to receive the margins of the side walls, and said side-walls being provided at their ends with joint strips folded to form locking Hanges adapted to engage the flanges of the joint strips on the end walls, and the marginal parts of which embrace the marginal parts of the said side walls.

20. The combination of end walls provided each with four joint strips, and bottom, top and side walls which are mitered at their meeting Aedges 'and provided at their ends with joint strips which interlock with those on the end walls` the bottom wall being provided at its ends with joint strips having flanges adapted to interlock with the joint strips on the end Walls, and at its side margins with joint strips having flanges adapted to form, with the mitered side edges, grooves toreceive the bottom edges of the adjacent side walls, and the top wall being provided at its side margins with joint strips, having flanges adapted to form, with its mitered side edges, grooves to receive the top margins of the adjacent side walls, and having on Vits endsl joint-strips folded to form flanges adapted to engage the flanges of the joint-strips on the upper margins of vthe end walls, Said flanges on the ends of the top wall being upwardly and outwardly mcllned .to permit their lateralentrance beneath the flanges on the said upper margins of the end walls bv downward or inward pressure on the said top wall.

21. The combination with a pair of meeting board members, of la metal joint strip on 'each of said meeting edges for locking the boards together, each strip being folded upon itself longitudinally to form a doublethlck interlocking flange and havinglits lateral marginal edges separated and formed to clasp the edge of its board, and a portion of one of s'ald marginal'parts bent to enter uch board and interlock the strip to the atter.

t FRED WILDER KEITH. Witnesses:

EMILIE ROSE, 'SAMUEL POND. 

